[Peripartum hemorrhage, diagnostics and treatment : Update of the S2k guidelines AWMF 015/063 from August 2022]

The current S2k guidelines on the diagnostics and treatment of peripartum hemorrhage are summarized in this article from the perspective of anesthesiology based on a fictitious case report. The update of the guidelines was written under the auspices of the German Society of Gynecology and Obstetrics with the participation of other professional societies and interest groups from Germany, Austria and Switzerland and published by the AWMF in 2022 under the register number 015/063.

[Prioritization of intensive medical treatment places - Concept proposal]

In the situation of a shortage of ventilation beds, ethically justifiable, transparent and comprehensible decisions must be made. This concept proposes that all patients are first intubated depending on necessity and then assessed by a triage team afterwards. In this situation newly admitted COVID patients compete with newly admitted Non-COVID patients as well as patients already treated in intensive care units for a ventilator. The combination of short-term and long-term prognoses should enable the interprofessional triage team to make comprehensible decisions. The aim of the prioritization concept is to save as many human lives as possible and to relieve the treatment team of the difficult decision on prioritization.

[Perioperative enhanced recovery after surgery program for Ivor Lewis esophagectomy : First experiences of a high-volume center]

BACKGROUND AND OBJECTIVE

Transthoracic esophagectomy is generally accepted as the standard of surgical care for patients with esophageal cancer. Despite improvements in the perioperative management this surgical procedure is associated with a clinically relevant morbidity. Fast-track protocols (synonym: enhanced recovery after surgery, ERAS) are conceived to perioperatively maintain the physiological homoeostasis and thereby to accelerate postoperative rehabilitation and reduce morbidity. In this prospective observational study the initial experiences of a high-volume center with the implementation of an ERAS protocol after transthoracic esophagectomy were analyzed.

MATERIAL AND METHODS

A total of 26 patients with esophageal cancer and a low index of comorbidities prior to hybrid Ivor Lewis esophagectomy were included in this study. According to an ERAS protocol all patients underwent a standardized perioperative treatment pathway aiming to discharge the patients from the inpatient treatment on postoperative day 10. The primary outcome parameter was the rate of major complications (Clavien-Dindo IIIb/IV), which was compared to a cohort of 52 non-ERAS patients.

RESULTS AND CONCLUSION

The ERAS programs with the various core elements can be implemented in patients scheduled for transthoracic esophagectomy, although the organizational and personnel expenditure of this fast-track protocol is high. The length of hospital stay appears to be reduced without compromising patient safety. The limiting variable of the ERAS protocol remains the early and adequate enteral feeding load of the gastric conduit before discharge on postoperative day 10.

[Acute treatment of pregnant women after severe trauma-a retrospective multicenter analysis]

BACKGROUND

For the medical team, the management of pregnant trauma patients is a particular challenge. The aim of this study is to compile this data and to determine differences between pregnant and not pregnant trauma patients.

MATERIALS AND METHODS

We carried out a retrospective data analysis from the TraumaRegister DGU® with a comparison of 102 pregnant and 3135 not pregnant women of child-bearing age (16-45 years) from 2016-2018 who were treated in a trauma center. All patients were delivered to the resuscitation room and received intensive care treatment.

RESULTS

In Germany, Austria and Switzerland 3.2% of all trauma patients (102 women) were pregnant. Women with an average age of 29 years suffered most often trauma as a result of a road traffic accident. Major trauma (Injury Severity Score [ISS] ≥16 points) was seen in 24.5% of the pregnant women and 37.4% of the nonpregnant women. A computer tomography (whole body computer tomography) was carried out in 32.7% of all pregnant women but in 79.8% of the nonpregnant women. As a result of the trauma, 2.9% of the pregnant and 3.5% of the not pregnant women died. The standardised mortality rate (SMR) was 0.42 in pregnant women and 0.63 in nonpregnant women.

CONCLUSION

For the first time there is data regarding incidence, trauma mechanism, prehospital and in-hospital care as well as intensive care of pregnant trauma patients in Germany, Austria and Switzerland. Further research regarding foetal outcome and trauma-related injuries in pregnant women is needed to develop an adjusted management for these patients ready to implement in trauma centres. Gynaecologists and obstetricians should be implemented in the trauma room team when needed.

[Selection of the optimal anesthesia regimen for cesarean section]

Approximately one third of all children in Germany are delivered by cesarean section. Depending on the individual patient's condition and the situation, the anesthesiologist has to choose between a general or a regional anesthesia regimen. The decisive factor for the selection is the obstetric urgency (decision-delivery time) after ascertainment of the indications. Furthermore, the need for postoperative analgesia varies depending on the chosen anesthesia regimen.

Intra-patient potassium variability after hypothermic cardiac arrest: a multicentre, prospective study

Background

To date, the decision to set up therapeutic extra-corporeal life support (ECLS) in hypothermia-related cardiac arrest is based on the potassium value only. However, no information is available about how the analysis should be performed. Our goal was to compare intra-individual variation in serum potassium values depending on the sampling site and analytical technique in hypothermia-related cardiac arrests.

Methods

Adult patients with suspected hypothermia-related refractory cardiac arrest, admitted to three hospitals with ECLS facilities were included. Blood samples were obtained from the femoral vein, a peripheral vein and the femoral artery. Serum potassium was analysed using blood gas (BGA) and clinical laboratory analysis (CL).

Results

Of the 15 consecutive patients included, 12 met the principal criteria, and 5 (33%) survived. The difference in average potassium values between sites or analytical method used was ≤1 mmol/L. The agreement between potassium values according to the three different sampling sites was poor. The ranges of the differences in potassium using BGA measurement were − 1.6 to + 1.7 mmol/L; − 1.18 to + 2.7 mmol/L and − 0.87 to + 2 mmol/L when comparing respectively central venous and peripheral venous, central venous and arterial, and peripheral venous and arterial potassium.

Conclusions

We found important and clinically relevant variability in potassium values between sampling sites. Clinical decisions should not rely on one biological indicator. However, according to our results, the site of lowest potassium, and therefore the preferred site for a single potassium sampling is central venous blood. The use of multivariable prediction tools may help to mitigate the risks inherent in the limits of potassium measurement.

Trial registration

ClinicalTrials.gov Identifier: NCT03096561.

Acupuncture reduces the time from extubation to 'ready for discharge' from the post anaesthesia care unit: results from the randomised controlled AcuARP trial

Acupuncture may improve peri-operative care as it reduces post-operative symptoms, such as pain, nausea and vomiting, or sedation. This patient-assessor blinded, randomised trial in 75 women undergoing gynaecologic laparoscopy evaluated the effects of acupuncture combined with a standardised anaesthetic regimen (ACU) on post-anaesthetic recovery, when compared to acupressure (APU) or standard anaesthesia alone (CON). Main outcome measure was the time from extubation to ‘ready for discharge’ from recovery as assessed by validated questionnaires. The main outcome differed significantly between groups (p = 0.013). Median time to ready for discharge in the ACU group (30 (IQR: 24–41) min) was 16 minutes (35%) shorter than in the CON group (46 (36–64) min; p = 0.015) and tended to be shorter than in the APU group (43 (31–58) min; p = 0.08). Compared to CON (p = 0.029), median time to extubation was approximately 7 minutes shorter in both, the ACU and the APU group. No acupuncture or acupressure-related side-effects could be observed. A difference in time to recovery of 16 minutes compared to standard alone can be considered clinically relevant. Thus, results of this study encourage the application of acupuncture in gynaecological laparoscopy as it improves post-anaesthetic recovery.

[Chest decompression in emergency medicine and intensive care]

Decompression of the chest is a life-saving invasive procedure for tension pneumothorax, trauma-associated cardiopulmonary resuscitation or massive haematopneumothorax that every emergency physician or intensivist must master. Particularly in the preclinical setting, indication must be restricted to urgent cases, but in these cases chest decompression must be executed without delay, even in subpar circumstances. The methods available are needle decompression or thoracentesis via mini-thoracotomy with or without insertion of a chest tube in the midclavicular line of the 2nd/3rd intercostal space (Monaldi-position) or in the anterior to mid-axillary line of the 4th/5th intercostal space (Bülau-position). Needle decompression is quick and does not require much material, but should be regarded as a temporary measure. Due to insufficient length of the usual 14-gauge intravenous catheters, the pleural cavity cannot be reached in a considerable percentage of patients. In the case of mini-thoracotomy, one must be cautious not to penetrate the chest inferior of the mammillary level, to employ blunt dissection techniques, to clearly identify the pleural space with a finger and not to use a trocar. In extremely urgent cases opening the pleural membrane by thoracostomy without inserting a chest tube is sufficient in mechanically ventilated patients. Complications are common and mainly include ectopic positions, which can jeopardise effectiveness of the procedure, sometimes fatal injuries to adjacent intrathoracic or - in case of too inferior placement - intraabdominal organs as well as haemorrhage or infections. By respecting the basic rules for safe chest decompression many of these complications should be avoidable.

[Perioperative management of transthoracic oesophagectomies : Fundamentals of interdisciplinary care and new approaches to accelerated recovery after surgery]

Locally advanced carcinomas of the oesophagus require multimodal treatment. The core element of curative therapy is transthoracic en bloc oesophagectomy, which is the standard procedure carried out in most specialized centres. Reconstruction of intestinal continuity is usually achieved with a gastric sleeve, which is anastomosed either intrathoracically or cervically to the remaining oesophagus. This thoraco-abdominal operation is associated with significant postoperative morbidity, not least because of a vast array of pre-existing illnesses in the surgical patient. For an optimal outcome, the careful interdisciplinary selection of patients, preoperative risk evaluation and conditioning are essential. The caseload of the centres correlates inversely with the complication rate. The leading surgical complication is anastomotic leakage, which is diagnosed endoscopically and usually treated with the aid of endoscopic procedures. Pulmonary infections are the most frequent non-surgical complication. Thoracic epidural anaesthesia and perfusion-orientated fluid management can reduce the rate of pulmonary complications. Patients are ventilated protecting the lungs and are extubated as early as possible. Oesophagectomies should only be performed in high-volume centres with the close cooperation of surgeons and anaesthesia/intensive care specialists. Programmes of enhanced recovery after surgery (ERAS) hold further potential for the patient's quicker postoperative recovery. In this review article the fundamental aspects of the interdisciplinary perioperative management of transthoracic oesophagectomy are described.

[Tuberculous encephalitis, Landouzy sepsis and Pott's disease: complications after surgery for spinal stenosis]

Tuberculosis is an infectious disease with a decreasing incidence in Germany. In particular, the occurrence of reinfections and possible complications associated with this disease, such as tuberculous meningitis/encephalitis and Landouzy sepsis are rare in industrial countries. In this article the intensive care treatment of a patient who initially underwent surgery for spinal stenosis is reported. Due to recurrent appearance of neurological symptoms with increasing severity and abscess formation in the spine, further surgery was performed. Additionally, the patient developed sepsis and meningitis. At this time an infection with Mycobacterium tuberculosis could be detected in both cerebrospinal fluid and abscess material of the spine suggesting a Landouzy sepsis, tuberculous meningitis/encephalitis and the suspicion of an underlying Pott's disease.

[Nutritional management of severely injured patients : Treatment between guidelines and reality]

Severe trauma triggers endocrine and inflammatory responses, leading to hyperglycaemia, insulin resistance and protein catabolism. Pharmacological and nutritional interventions cannot counteract these metabolic disturbances. However, adequate supply of energy and proteins may reduce excessive catabolism.Available guidelines recommend early use of enteral nutrition with energetic supply of about 25 kcal/kg and additional protein supply of 1.5 g/kg/day. These aims will be missed frequently by solely providing enteral nutrition in severely injured patients. Early supplemental parenteral nutrition should be used in these cases. Concomitantly, gastric paresis and paralytic ileus hampering enteral nutrition should be treated by propulsive and prokinetic drugs and by use of duodenal or jejunal site of application in selected cases.Euphoric hopes linked with intensified insulin therapy (IIT), targeting blood glucose levels <110 mg/dl in intensive care patients, had to be widely abandoned in recent years. The goal for blood glucose levels should be set at 180 mg/dl as the upper limit according to current knowledge, which promises to optimize the balance between efficacy and safety.

Inosine, not adenosine, initiates endothelial glycocalyx degradation in cardiac ischemia and hypoxia

Ischemia/reperfusion and hypoxia/reoxygenation of the heart both induce shedding of the coronary endothelial glycocalyx. The processes leading from an oxygen deficit to shedding are unknown. An involvement of resident perivascular cardiac mast cells has been proposed. We hypothesized that either adenosine or inosine or both, generated by nucleotide catabolism, attain the concentrations in the interstitial space sufficient to stimulate A3 receptors of mast cells during both myocardial ischemia/reperfusion and hypoxia/reoxygenation. Isolated hearts of guinea pigs were subjected to either normoxic perfusion (hemoglobin-free Krebs-Henseleit buffer equilibrated with 95% oxygen), 20 minutes hypoxic perfusion (buffer equilibrated with 21% oxygen) followed by 20 minutes reoxygenation, or 20 minutes stopped-flow ischemia followed by 20 minutes normoxic reperfusion (n = 7 each). Coronary venous effluent was collected separately from so-called transudate, a mixture of interstitial fluid and lymphatic fluid appearing on the epicardial surface. Adenosine and inosine were determined in both fluid compartments using high-performance liquid chromatography. Damage to the glycocalyx was evident after ischemia/reperfusion and hypoxia/reoxygenation. Adenosine concentrations rose to a level of 1 μM in coronary effluent during hypoxic perfusion, but remained one order of magnitude lower in the interstitial fluid. There was only a small rise in the level during postischemic perfusion. In contrast, inosine peaked at over 10 μM in interstitial fluid during hypoxia and also during reperfusion, while effluent levels remained relatively unchanged at lower levels. We conclude that only inosine attains levels in the interstitial fluid of hypoxic and postischemic hearts that are sufficient to explain the activation of mast cells via stimulation of A3-type receptors.

Shedding of the coronary endothelial glycocalyx: effects of hypoxia/reoxygenation vs ischaemia/reperfusion

BACKGROUND

Vascular endothelium is covered by a glycocalyx. Damage to the glycocalyx after systemic inflammation or ischaemia/reperfusion contributes to increased vascular permeability and leucocyte adhesion. The underlying mechanisms leading to ischaemia/reperfusion-induced glycocalyx shedding are incompletely understood, in terms of lack of oxygen, absence of flow, or return of oxygen.

METHODS

Isolated guinea pig hearts perfused with Krebs-Henseleit buffer at 37°C underwent 20 min of either stopped-flow ischaemia or hypoxic perfusion with subsequent reperfusion/reoxygenation (n = 6 each). Hearts perfused with normoxic buffer served as time controls. Epicardial transudate was collected to assess coronary net fluid filtration, colloid extravasation, and histamine release by mast cells. Syndecan-1 and heparan sulphate were measured in coronary effluent, together with lactate, purines, and the release of mast-cell tryptase β. Additional hearts were perfusion-fixed to visualize the glycocalyx.

RESULTS

Both ischaemia and hypoxia with reperfusion/reoxygenation resulted in significant increases in net fluid filtration (P < 0.05) and release of syndecan-1 and heparan sulphate in coronary effluent. These effects were already seen with the onset of hypoxic perfusion. Histamine was released during hypoxia and reoxygenation and also reperfusion, as was tryptase β, and high concentrations of adenosine (>1 µmol litre⁻¹, hypoxia group) and inosine (> 7 µmol litre⁻¹, ischaemia group) were measured in effluent (P < 0.05). Damage to the coronary glycocalyx was evident upon electron microscopy.

CONCLUSIONS

Both ischaemic and hypoxic hypoxia initiate glycocalyx degradation, promoting an increase in permeability. A contributing mechanism could be purine-mediated degranulation of resident mast cells, with liberated tryptase β acting as potential 'sheddase'.

Lung injury following thoracic aortic occlusion: comparison of sevoflurane and propofol anaesthesia

BACKGROUND

Halogenated anaesthetics have been shown to reduce ischaemia-reperfusion injuries in various organs due to pre- and post-conditioning mechanisms. We compared volatile and total intravenous anaesthesia with regard to their effect on remote pulmonary injury after thoracic aortic occlusion and reperfusion.

METHODS

Eighteen pigs were randomized after sternotomy and laparotomy (fentanyl-midazolam anaesthesia) to receive either sevoflurane or propofol in an investigator-blinded fashion. Ninety minutes of thoracic aortic occlusion was induced by a balloon catheter. During reperfusion, a goal-directed resuscitation protocol was performed. After 120 min of reperfusion, the anaesthetic regimen was changed to fentanyl-midazolam again for another 180 min. The oxygenation index and intra-pulmonary shunt fractions were calculated. After 5 h of reperfusion, a bronchoalveolar lavage was performed. The total protein content and lactate dehydrogenase activity were measured in epithelial lining fluid (ELF). Alveolar macrophage oxidative burst was analysed. The wet to dry ratio was calculated and tissue injury was graded using a semi-quantitative score. Ten animals (n=5 for each anaesthetic) without aortic occlusion served as time controls.

RESULTS

The oxygenation index decreased and the intra-pulmonary shunt fraction increased significantly in both occlusion groups. There were no significant differences between sevoflurane and propofol with respect to the oxygenation index, ELF composition, morphologic lung damage, wet to dry ratio and alveolar macrophage burst activity. Differences were, however, seen in terms of systemic haemodynamic stability, where catecholamine requirements were less pronounced with sevoflurane.

CONCLUSION

We conclude that the severity of remote lung injury was not different between sevoflurane and propofol anaesthesia in this porcine model of severe lower-body ischaemia and reperfusion injury.

Validation of pulse contour derived stroke volume variation during modifications of cardiac afterload

BACKGROUND

Left ventricular stroke volume variation (SVV) or its surrogates are useful tools to assess fluid responsiveness in mechanically ventilated patients. So far it is unknown, how changes in cardiac afterload affect SVV. Therefore, this study compared left ventricular SVV derived by pulse contour analysis with SVV measured using an ultrasonic flow probe and investigated the influence of cardiac afterload on left ventricular SVV.

METHODS

In 13 anaesthetized, mechanically ventilated pigs [31(SD 6) kg], we compared cardiac output (CO), stroke volume (SV), and SVV determined by pulse contour analysis and by an ultrasonic aortic flow signal (Bland-Altman analysis). After obtaining baseline measurements, cardiac afterload was increased using phenylephrine and decreased using adenosine (both continuously administered). Measurements were performed with a constant tidal volume (12 ml kg-1) without PEEP.

RESULTS

Neither increasing mean arterial pressure (MAP) [from 59 (7) to 116 (19)] nor decreasing MAP [from 63 (7) to 39 (4)] affected CO, SV, and SVV (both methods). Method comparison revealed a bias for SVV of 0.1% [standard error of the mean (SE) 0.8] at baseline, -1.2% (SE 0.8) during decreased and 4.0% (SE 0.7) during increased afterload, the latter being significantly different from the others (P<0.05). Thereby, pulse contour analysis tended to underestimate SVV during decreased afterload and to overestimate SVV during increased afterload. Limits of agreement were approximately 6% for all points of measurement.

CONCLUSIONS

Left ventricular SVV is not affected by changes in cardiac afterload. There is a good agreement of pulse contour with flow derived SVV. The agreement decreases, if afterload is extensively augmented.

Effects of sevoflurane and propofol on ischaemia–reperfusion injury after thoracic-aortic occlusion in pigs

BACKGROUND

Thoraco-abdominal-aneurysm surgery predicts high mortality. Propofol and sevoflurane are commonly used anaesthetics for this procedure. Halogenated anaesthetics induce organ protection similar to ischaemic preconditioning. We investigated which anaesthetic regimen would lead to a better protection against ischaemia-reperfusion injury induced by temporary thoracic-aortic occlusion.

METHODS

Following initial fentanyl-midazolam anaesthesia for surgical preparation, 18 pigs were randomly assigned to two groups: group one received propofol (n=9) and group two sevoflurane (n=9) before, during, and after lower body ischaemia in an investigator blinded fashion. Ten animals without aortic occlusion served as time controls (propofol, n=5; sevoflurane, n=5). For induction of ischaemia, the thoracic aorta was occluded by a balloon-catheter for 90 min. After 120 min of reperfusion, the study anaesthetics were discontinued and fentanyl-midazolam re-established for an additional 180 min. Goal-directed therapy was performed during reperfusion. Fluid and catecholamine requirements were assessed. Serum samples and intestinal tissue specimens were obtained.

RESULTS

Severe declamping shock occurred in both study groups. While norepinephrine requirements in the sevoflurane group were significantly reduced during reperfusion (P<0.05), allowing cessation of catecholamine support in 4/9 animals, all 9/9 animals were still catecholamine dependent at the end of the experiment in the propofol group. Serum activities of lactate dehydrogenase, aspartate transaminase, and alanine aminotransferase were lower with sevoflurane (P<0.05). Small intestine tissue specimens did not differ histologically.

CONCLUSIONS

Use of sevoflurane compared with propofol attenuated the haemodynamic sequelae of reperfusion injury in our model. Release of serum markers of cellular injury was also attenuated.

Pulmonary graft function after long-term preservation of non-heart-beating donor lungs

BACKGROUND

Critical organ shortage in lung transplantation could be attenuated by the use of non-heart-beating donor (NHBD) lungs. In addition, prolonged ischemic tolerance of the organs would contribute to the alleviation of organ shortage. The aim of this study was to investigate pulmonary graft function of NHBD lungs after long-term hypothermic storage.

METHODS

Twelve native-bred pigs (bodyweight 20 to 30 kg) underwent left lung allotransplantation. In the heart-beating donor (HBD) group, lungs were harvested immediately after cardiac arrest. In the NHBD group, lungs were subjected to a warm ischemic period of 90 minutes before harvesting. After a total ischemic time of 19 hours, pulmonary grafts in both groups were reperfused and pulmonary graft function was assessed. All values were compared with a sham-operated control group.

RESULTS

Pulmonary graft function in the HBD group was excellent. In the NHBD group, pulmonary gas exchange was impaired, but still provided good graft function compared with the excellent graft function in the HBD group. Pulmonary vascular resistance was even lower in the NHBD group. In the NHBD group, calculated intrapulmonary shunt fraction (Qs/Qt) was significantly increased compared with the sham-group. Histologic alteration and wet-to-dry ratio did not differ significantly between the HBD and NHBD group.

CONCLUSIONS

We conclude that NHBD lungs (90 minutes of warm ischemic time) have the potential to alleviate organ shortage in lung transplantation even after an extended total ischemic time.